Hairline crack in my hedder tube.

Today I swapped a starter relay on the 66 Dart,while doing this I caught a glimpse of a mark on my coated headers.These are Hedman Husler,s fenderwell hedders that are coated.Upon further inspection,I noticed a very small crack(about 3/4 inch) starting at #3 cyl. tube on the outer side of the weld.These hedders weren,t cheap and I,ll be calling the manufacture about this,cause they,re only 6 mnths old and see what they have to say.I,ll post pics of the hairline crack tomorrow.I,ve heard the best way to stop from cracking is to drill little holes at the end of each side,then weld up.Has anybodyelse had a problem like this and what did you do?Thanks.
Here,s a pic of the hedders..
View attachment car pics 66 Dart 135.jpg

View attachment car pics 66 Dart 136.jpg

View attachment car pics 66 Dart 137.jpg

View attachment car pics 66 Dart 196.jpg